Artificial arm and hand and actuating means therefor.



E. w. HOBBS. V ARTIFICIAL ARM AND HAND AND AOTUATING MEANS THEREFOR.

APPLICATION HLED WAR. [9, I911.

11,253,823. Patented Jan. 15, 1918.

3 SHEETSSHEET I.

L. View E. W. HOBBS.

ARTIFICIAL ARM AND HAND AND ACTUATING MEANS THEREFOR. APPLICATION FILEDnAn.|9.1911.

1,253,823. 7 Patented Jan.15,1918.

3 SHEETS-SHEET 2.,

Ila/m3 n E. W. HOBBS.

ARTIFICIAL ARM AND HAND AND ACTUATING MEANS THEREFOR.

APPLICATION FILED. MAR. 19. 19M.

51,253,823. Patented Jan.15,1918.

3 SHEETS-SHEET 3.

UNITED s'rAT s rarer-vii? OFFICE. if

EDWARD warren Horns, orstinnnr, ENGLAND.

ARTIFICIAL ARM AND HAND AND ACTUATING MEANS THEREFOR.

Specification of Letters-Patent.

Patented J an. 15, 1918.

Application filed March 19, 1917. Serial No. 155,878;

1 '0 all whom it may concern:

Be it known that I, E WARD ,Warxren House, a subject of the King ofEngland, residing in Surrey, England, have invented certain new anduseful Improvements in Artificial Arms and Handsand Actuating MeansTherefor, of which the following is a s )ecification.

his invention is for improvements in or relating to artificial armsandhands, and

actuating means therefor and has for its object to provide improvedmechanism whereby the artificial. limb may, under the volition of thewearer, efi'ect movements performed by the natural limb for which it isadapted to act .as a substitute.

, The invention isapplied. to artificial arms of the type in which aharness is fitted about the chest and shoulders of the'wearer, and

cords. or the like operatively connect the artificial limb with theharness sothat the limb may be actuated-by muscular action oftheharnessed part of the wearers body.

. In the accompanying drawin sv Figure 1 is a general view of anartificial arm and hand adapted to be, used when the arm. has beenamputated above the elbow Figs. 2 and 3 are a side elevation and planrespectively of the mechanism for eflecting the movement of the fingers;

Fig. 4 is a detail of the wrist-construction; p

F ig..5 is aside elevation, partly in sec tion, of a modifiedCOIlStI'IlC'DlOIl of fingeroperating mechanism v i Fig. 6 is a plan ofthe same;.,. 1

. Fig. 7 is .a detail of hetfinger-operating mechanism and i Fig. 8shows an alternative link-mechanismfor the fingers. Likereferencecharacters denote like parts throughout the drawings. i I

1, The'artificial hand new about to be; described is; attached to theforearm by a suit- :able wrist j oint whichis adapted to give twomovementszto the handyoneua rotation about the longitudinal axis of theforearm, and the other a bending movementaboutgan .axistransverse to:the forearm,. Fight-shows the arrangement of the wrist .-joint-=itor thebendingmovement, this view being a, section at right-angles tothat-illustrated in]? ig,,1 and on alarger scale. T heendof theorearm Ais closed by a plate Af in-which.-there i entrally m m ed. t el, 01:. oher; s itably strong tube A This tube, as will be i i center, thisturning constituting the bend.-

ing ofv thehand relatively to the forearm. The control of this movementis effected by providinga notched Plate A constituted by .an. extensionof the bracket AT (or secured on thebr ackefliand,av detent B pivoted at{Eton the body of the hand, and provided with a tongue'B? to engage. thenotches in the plate A. Aspring is used to hold the lever B in itsengaging osition, and the end of the lever j projects mtothe palm of thehand near the wrist so that it may be actuated by the other hand ofthewearer. Thus, when the user wants to flex the hand at the wrist, thelever B is moved to dis engage the lug B? and thehand moved to thedesired position when the lugB is allowed. to engage with another notch.As shown inFig. 1, three notches are provided corresponding. to. threepositions of the hand, as this is found to be suflicient in practice tosatisfy-all ordinary requirements.

I ,Theamechanism for obtaming the other wrist rnovement, that is to sayarotation of thehand about 1 the J longitudinal; axis of the foreanmidoesnot form any. part of th s, invention and it, need only be. pointed outthat suchvmechanism is desirable to render 'the artific ial hand asuseful aslppssible.

. The mechanism for operatingthe fingers andthumb ofga mechanical handis illus tratedin Figsr2 and 3, andis also shownin Figs. 1, 5 andtinpositionona hand. Referring.- to Figs. 2, and 3 the mechanism consistsofa.- base-plate E provided with two undercut recesses or grooves E E oneof, these: grooves there is, mounted a slider Eiand-it isprovidedat oneend with ,gnoperatingcord E! which extendsup the earn and-is connectedto the. usual bod wheeler; ithewee r op r te:

which is operative to return it to nal position after it. myfld lll'rltguide E by the cord E 5 The second sgmov-e.E vinthe base plaiteris.

Weiilgf frfiember 513 the move itfwhenjthe "s'l ider is jrhovefl pullingon the cord E.

sprih"" E or other resilient control. 'il ar to t at oh the "slider,isprovided forth? .fanfeifis arranged to move the? Wedge a'dHection'whieh its 'thiekei end is in item; Thatisto say,-When the Wedge E is"moved by pulling" on the cord E the wagin face-is in front, but when itis moved Ihaektvar'd' by the spring E the wefd ging face is behind.

A jlra'ke or; clet'ent is provided to hold the 'W edgein any position toWhih it has been movea; Kbrake-"shoe F is mounted on'a fsleef 'vejliweenie free to turn on a vertical spindle fixed ofn the ease E, thedisposif-tlri arrangement or the ewe being Such that it acts trjitinaliylike the pawl bf ratchet, and does-ndt restri'eflappre'eifablyany'movement '=oiE the wedge to"ward *the frightin Figs? and- 3; itfloeshoweyer, preylltlffi ovil'riefititOwhlfel ifih'e' 18 51;. The sleeve Falso carries an arm 'F whieh extends aefoss the baseboard andcarries apawl F :at" free end; "1h rs" paw 1 is "controlled by "a; F topr'ojectin ra the'j'p'a-th of *a pin F Un t-he slider E' ajnd a stop F on thearmFF =1iniits the movement of the pawl F in one direaien. Thearrangemefltis such jflhag when the-slider E is mevedro theright 3 theski- 1 *ngages' thepavvl F -vxflii' -eoiitarfjwith the stop"fhe I6 "pin"*1? "removed "f enema e -i Ht; The-"whitened was skewer; ind e?"slidentakes --plaee-before the slider engages the Wedge te n io e jg Asprigg -lf holds the arm F "norm ly in the position in which the brakeismpplied towthe, Arspindle G is mounted near the base-hoard With. itsaxis tramsvense to the line of movement of .--the Wedge and it carries athree-arfned lever hr equiValeiitdevi-ee which, as shown con sists of atriangular plate G; At one end this plate carriesa roller (fir whichlies on 'th {inEIined surface F of the Wedge E, hatm vemem of Wedge inits groove ca tn-apnea GE-to leerocked about the pindle e nter'.Anet11e1 c0111er of theplate is connected by a'iihk G tfo't he 'fin gerop'eratihg 'nieeh an'1'srh,- aid the third corner of the plate isoonnecte'dhy aiink G "to the thurnb' foroperating the same In thepreferred 'c onstrtitftion, the plate G is stifi'ened and reiiiioreed byan additional linl G"Whieh receives the pivotal connee tion for thethuI'nb I ink-G Referringnon to Fig. l, the connection of the mechanismillustrated in Figs. '2 and 3 to the fingersfls "illustrated.

B Thefiii'ger corlsists'aaf two Phal'anges H H T he firstf] :'1'l'1"alan'x II- is pivoted at H on to of the and the =s'eeon'd 11mm is;pivoted "git H on "to thefirs't phaltinki "The-link G referred to above,is connected to "the "phalanx by a pivotal]. conneeti on and he linkitself has an extension Whiich ies at aan' obtuse angle with "the'part Gthereby forming a. beller'ank' lever, and has pivotal connection, atitsend Gfihvith' -a link H. The other end ofithisdink i's p'ivoted'at Hon the second phalanx; The pivot H is so positioned relatively" to thepivot H "that a pull on 'tlie'Tod-G -causes the first phalanx-to swingupward in the position for closing the fin- 12ers. f Thef-pivot-poi nt Gis arranged to lie en the opposite side of the line j oinia'ag thepoints H H f re the pivotqmir rt+1511. Then the phallatnx re -swunguppart iG oit he lirfii hsvs t thrfiifig dnovementmbout the pivot Hrelatively to th=phahin x- H, or, in other words, t'd 'tlie lifiedff-"eeriters 1E "H This relative turning nmwmmgives a'pull ori 'thelink *H "that theaoi'ilter 'halanx H is caused to turn on pivot *rliitivel'y to the ii-mar 'pha lanx H'. "This relafive unaiing meveagenti s superposed on the movement ofthe fir'st ply-sham, so that the*segondphflam folded dawn until of the fingemppmeh s the palm dffihilifl igw 'i't I lt vj' these e11 tlih the-link G eon stitfitesafi-ceaialiflg rdd" tween two -virt1-1 a 1 crank maginedt-1: These ermksa prfiel'ablv neq eal 1ength;=-

the p b not pifrlfllefi the-arrangefiiie'tit bufg thet a sh'ialleirglilar"mere- 'fihflflfiEh'Qflfiik a caiifss e hre inguhr 1fiibirfnent o'f the (frank tha -1mg the initial y' arr {of themovement.- Instealdi of nsmg the'crank a jthe parts may be so arran'ged""(fb'r 'ex'iiinplg corl'neted to a cord from the harness) that 'aldii'ect'piill is applied to the linlfGfif hut the-operation of the linkageii the same; Fnricher," it will be seen that the phalanx I H constitutesone member ofa lmlt-niechzmism"H G and file virtual crank between thepivots H H, snehlinkw e efi ecting the mwement f the outer p'alanXH. 1

1 Similar mechanism may be provided for eaeh'efthe other. fijng'ers, inwhich, ease "eachtvonlwbe pr0t 1*&ed"With a link' corre- "spending tothe link G and this link Won lid benibved by'u radial arm mount'e'clen tshiift G extending transversely of the palm of the hand;

fThe thumb is provided with. one movable phalanx H" andthi-s is directlyebnnctefd with thelink G which, in the arrangement *shown ismlesigned toexert a thrust onth teilo'n-the phalanx 'so 'tts to cause it to bebentageinst'the action 'of a spring H. in. thesame manner as anatnralthninh. ,7

The link-mechanism for-Q ereting" the fingers constitutes s kind (ifoggle-inecha- *nism so that eo'rrsidemblecthree-jean be exer'tetl bythefingers wgrip anyartic' le that is desired. The opening of the fingersUnder 3 this pressure is prevented= by -so-'-arranging the wedge thatthe fnebhanism is notr'e- 'ver'sibler The proportins oi'f'the parts ofthe plate G are so arranged that the pres-- sure of theroller G on theWedge-surface F is alwziys app'roximtitely normal to the "lisse pltite'E tihl the afiglefof'the Wedge is 'sufli-ciently small to'insure thatthe hori- "zontal commenter this thrnst, tending to "move the Wedgealong the base-plate,' is in- "sn-iiici'ent to overcome the friction.The bi'sik'e'shoe' F, j dSCI'i'bGd above, acts as a i thither safeguard.1 to prevent an 7 sueh mdveiileiit. H

f The operation of this mechanism tfqflowg'gf i ruinl 1, -Y Assumingthatthe fingers ere tr11ghti in theposition-indicated in Fig; 1-, anclthat it isdesired'tb' elo'se them, apuil-is exerteden the eordmEt bymeanspi? the'harness; This pull I'n'oves the-Slider E which releases thebrake]? antithen moves th-WedgeE: The plum G? is" rocked about its ivotG by the engagement "of the roller G -with the wedge fec'ei Fig find fapull is im arted to "the link am'wljthirirstto*the*lin G. r 'IheIink Gp'in F"r'ides past the 'iwlF which yields, under the centrol'of thespring 'Fifand eturns to its original position.

If, now, it is 'desi'red to open the fingers,

a slight pull on thee'ord E inoi esthe' slider inal position bye springH" engaging the end phalanx of the thumb. Ihespring is errehgedthetiitis'compressed when the thumb (and fingers) are flexed, 'andfit thereforeOperates to. return theni "when released.

.The piv0t-pins by which the links are secared to the fingers or otherparts of the hand; are illustrated in Fig. 7. Generally speaking,thephalzul'ges of the fingers 'are mad-eof wood or similar lightmaterial and the "linkszi-re of metal; It is desirable to keep thepiV'0t'pins smell, in Order that the fric" tion .of the l nks 'on themis redupd 'td""a ininirntim, but sinall pivot-pins 'yery rapidly heiiomeloose'in the n oodenpart 'ofthe fiiigi' iii' tiliieli they are mounted.A'subsidiiir' feature of this invention 'eonsists in the Construction ofpivot-pinshown in Fig-r7. The pivot-pin is formed with a rediicethpart Jupon which the link J bears, and "a "heiigl- 5 of larger diameter thanthe part J, is provided. A-Coned sii'rfaee connects the two parts." Anut J similar in dimensions to the head Jfi i's' screwed on to the otherend of the pin J and it'inay bepinned thereto if desired. The twoenlargements,.J J constitute a? support for the pivot pin ,iii theWoodenpzii't 6f the hand or finger end the are of suitable largedimensions. The mi stit'ntes' a suitably-smell bearing for the link '1The .co'n'ed fsui'feees on the two enlar'g eprovide means for takin upsleek or fwear 1n the "beer-mg y ereiving fthefniltdl somewhat fartheron were pin 1 alt'rn'atii e ednstruction'j oft mechanism for operatingthe fingers-"19 illustrated in Fig. 8. The first" phalanx H iso andpartly by the radius of action of the roller G on it, since all that isrequired is to impart a certain movement to the links G G This movement,in turn, governs the situation of the pivotal connections to thephalanges. Similarly, the linkage for the different fingers may bevaried so that when they are operated simultaneously they open or closein varying degrees so as to simulate more exactly the natural action ofthe hand.

The proportioning of the finger linkage G H and the positioning of thepivotal connections can be varied according to the force which it isrequired to exert by the fingers in closing.

Finally, it may be pointed out that in order to obtain a good frictionalhold on objects touched, the tips of the fingers may be made of rubberand spring-steel fingernails may be provided. In this way, actions suchas turning over the pages of a book, or opening pocket-knives, may bereadily effected. The steel nails, of course, also assist in stifl'eningthe rubber-tips if such stiffening be necessary.

WhatI claim as my invention and desire to secure by Letters Patent is 1.In an artificial hand, the combination with a movable part thereof, of areciprocatable wedge, a rocking member engaging an inclined face of saidwedge to be rocked by the reciprocation thereof, and an operativeconnection between said rocking member and said'movable part.

2. In an artificial hand the combination with a movable member ormembers of the limb, of a reciprocatable wedge to work them, areciprocatable slider movable alongside the wedge and actuated by theatient, returning-springs for the wedge an slider, a brake or detentacting on the wedge, a brakeor detent-releasing lever, a brake applyingspring and projections from the slider that in its forward stroketemporarily release the brake or detent and actuate the wedge, theconstruction of the brakereleasing lever and rojections being such thatthe former is on y operated in the forward stroke of the latter.

3. In an artificial hand, the combination with a movable finger thereof,of a rocking shaft, an arm on said shaft, a link connecting said arm tosaid finger, a reciprocatable wedge, a second arm on said shaft engagingthe wedging face of said wedge, and inde' pendently operated meansengaging said Copies 0! this patent may be obtained for second arm todisengage it from said wedg ing face when required.

4;. In an artificial hand, the combination of a reciprocatable wedgemounted in the palm of the hand, a rocking lever whereof one arm engagesan inclined face of said wedge, a movable finger comprising twophalanges whereof the first is pivotally connected near one end to thepalm of the hand and the second is pivotally mounted near the free endof the first, a link connected to a second arm of said rocking lever andto said first phalanx at a point eccentric from its pivotal axis, acranked extension on said link shaped to cross the line connecting thetwo pivotal axes of the two phalanges when these phalanges are in linewith one another, a second link connecting the end of said crankedportion to a. point on the second phalanx, which point is eccentric fromthe pivotal axis of said second phalanx.

5. In an artificial hand the combination with a plurality of movablefingers of a reciprocatable wedge, a rocking member engaging an inclinedface of said wedge and rocked by the reciprocation thereof, and anoperative connection of different VclOClt ratio between said rockingmember and eac of said fingers.

6. In an artificial hand the combination of two grou s of movablefingers, a reciprooatable wec ge, two rocking members engaging saidwedge, an operative connection between each group of fingers and one ofthe rocking members, and means for selectively disengaging said rockingmembers from said wedge.

7. In an artificial hand, the combination with a phalanx pivoted on thepalm and a second phalanx pivoted on the first, of an operating linkpivoted at one end to the palm of the hand at a point (Q lying on a lineapproximately at right-angles to the line joining the pivot points ofthe phalanges, and at the other end to the second phalanx at a point (Qeccentric from the pivot point of that phalanx.

S. In an artificial hand, means for moving one member relatively toanother comprising a crank engaging a push-rod. which 1n turn engages aseries of balls in an inextensible conduit and a second push-rodoperatively connected to the member.

In testimony whereof I have signed my name to this specification.

EDWARD WALTER HOBBS.

five cents each, by addressing the Commissioner of Patents,

Washington, D. O.

